The present invention relates to a machine control system for a machine or plant with a plurality of functions controlled by start signals and stop signals, which are input by means of a data processor (computer) with a display screen.
A machine control system of this kind is generally known.
In this known control system, it is possible to release functions by hand, in that the data processor associated to the machine being controlled is caused, for example, by means of the keyboard of the control system, to release the start signal, so that the machine performs the particular function. In this connection, there are also machines which are capable of performing and intended to perform a plurality of functions at the same time, and/or successively, and/or with a time overlap.
When the machine is intended to perform a plurality of functions in a predetermined, chronological sequence, the start signals of the functions may also be released by a timing device of the data processor instead of by hand. In this instance, the timing device receives its input command for recording the time by the start signal or by the stop signal of another function that preceded in time.
The end of the function may again be released by hand. However, the data processor may also include a timing device which causes the stop signal of the function to be released after the lapse of a predetermined time, and which stops the function. It is possible to perform the time recording of even this timing device by the start of same, or by another function, or by the end of another function.
In general, the named timings are adjustable. In this connection, the enumeration of the possibilities of controlling the machine is by no means complete, but only by way of example.
In such a machine control system, there exists the risk that the unclearness of the existing functions leads to faulty switchings. Primarily, this applies to the event, when a plurality of functions is to be switched and run, that a function is missed, or that the relative, chronological switching points are wrongly selected and lead to a mutual interference of the functions.
In accordance with one aspect of the present invention, a control system in designed and constructed to operate in such a simple and transparent manner that the functions are safely preselected and switched in the correct sequence, at the right times, and with the right duration.
In accordance with one aspect of the present invention, the control system is for a machine or plant that performs a plurality of functions during an operating cycle, with each function being initiated by a start signal and ceased by a stop signal. In accordance with this aspect, the control system includes a computer and a display screen, and the computer is for performing the operations described below. The computer stores a plurality of display screen signals respectively corresponding to the functions. Each display screen signal includes starting and stopping limits, and the duration of the corresponding function is defined between the starting and stopping limits. The computer uses the display screen signals to graphically illustrate the functions and the duration of the functions on the display screen. Preferably the functions are graphically illustrated on the display screen in the form of parallel lines. The computer controls the operating cycle by causing a switching signal to advance in time in a direction that corresponds to the direction from the starting limit toward the stopping limit of each display screen signal. For each display screen signal, the computer provides the start signal for the corresponding function when the switching signal coincides with the starting limit, and the stop signal is provided for the corresponding function when the switching signal coincides with the stopping limit.
In accordance with one aspect of the present invention, the functions are graphically illustrated on the display screen in the form a bar diagram, with each bar of the bar diagram corresponding to a respective one of the functions and extending in the same direction as a time axis. The bars can be arranged in rows or columns. For each function, its corresponding bar has opposite ends that identify positions along the time axis that correspond to the starting and stopping limits of the screen signal for the function. The switching signal travels in the direction of the time axis and for each function the start signal is provided when the switching signal corresponds with one of the ends of the bar corresponding to the function, and the stop signal is provided when the switching signal corresponds with the other end of the bar corresponding to the function.
In accordance with one aspect of the present invention, the switching signal is illustrated on the display screen and travels in the direction of the time axis. For each function, the start signal is provided when the mark is aligned with one of the ends of the bar corresponding to the function, and the stop signal is provided when the mark corresponds with the other end of the bar corresponding to the function.
The present invention has as the advantage that it makes it possible to possible to predetermine the beginning or end, as well as the relative time slot of the functions, selectively by hand or by stored sequences and time durations.
The present invention can be used with special advantage in mining for rearranging longwall support devices, i.e., mining shields, since there the start of the rearrangement cycle is automatically predetermined, a large number of functions is to be switched, and since the chronological sequence of the individual functions relative to one another is to be preselected under difficult conditions.